Cao Cao

State · 197–223 CE · at its largest around 215 CE

Domain of the warlord Cao Cao, who controlled northern China and the Han court at the end of the Han dynasty; his son Cao Pi founded the Wei dynasty.

On its lands while it lasted

Han dynasty (202 BCE – 220 CE): Liu Bang founded the Han dynasty, a formative imperial age whose name became that of the majority Chinese ethnic group.
Goguryeo (c. 37 BCE – c. 668 CE): Kingdom traditionally founded by Jumong in 37 BCE that grew to rule northern Korea and Manchuria.
Gungnae (c. 3–427 CE): Capital of Goguryeo (3–427).
Cao Cao (155 CE – 220 CE): Warlord and chancellor of the late Han who unified northern China; his son founded the state of Wei.
Yellow Turban Rebellion (184–205 CE): Peasant uprising led by the Taoist healer Zhang Jue that fatally weakened the Han dynasty and empowered regional warlords.
Three Kingdoms period (220–280 CE): After the end of the Han, China was divided among the states of Wei, Shu and Wu.